SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9787501706ca23823f5026759b931c3e1da8f035221fd3c5d24f044a90c3e1f2' 
  AND token = 'Jaj8KQotZIsCVzl3BuZUxKzgVvhEgUDdRpKLfwXSW4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}